1. Field of the Invention
This invention relates to protective drainage devices used for protecting masonry walls from moisture contact and infiltration, and more particularly, to drainage plate systems useful for protecting foundations and basements from ground water contacting and infiltrating such foundations and basement wall structures.
2. Brief Description of the Prior Art
In protecting the walls of basements, or other below-grade foundation walls, from deleterious contact with ground water, various proposals have been advanced for shielding these structures. In the simplest form, it has been proposed to coat them with tar or a viscous, settable or thixotropic sealant material which seals the pores of the masonry and prevents water infiltration. Some of these films or coatings have hydrophobic characteristics which tend to turn away or repel the water which comes in contact therewith, and thus effectively shield and protect the below-grade foundation or basement wall.
In other arrangements, some of which have been patented, it is proposed to place adjacent the portion of the wall which is below grade, a synthetic resin structure which blocks the water from contact with the wall, and affords vertical channels to allow the water to drain downwardly to the bottom of the wall where it is then carried away in a perforated footer pipe, or some similar water-collecting structure. In some types of construction, the perforated footer pipe placed at the bottom of the foundation or basement wall is embedded in a bed of gravel placed in a pit below the protected wall.
One arrangement which has been patented and which is of the general character described is the vertical drainage system shown in U.S. Pat. No. 3,704,362. Here a mat or body of thermoplastic filaments is placed over the coated outer side of a basement wall between the wall and the earth. Water drains downwardly through these filaments to a perforated pipe disposed at the lower end of the filament mat, and this pipe collects the percolating water and drains it away from the protected wall.
A protective membrane having corrugations formed therein for spacing the membrane from a foundation wall to be protected, and to provide air channels between a protective sheet and the foundation wall, is illustrated and described in U.S. Pat. No. 3,888,087. Small vertical ribs are provided on the membrane to provide water channels to allow the water to drain down the membrane to the bottom of the foundation wall. A drainage pipe is located adjacent the footing at the bottom of the foundation wall for picking up and disposing of water which has drained down the protective membrane. Another patent showing a structure of this general type is U.S. Pat. No. 4,142,344. A channelized protective structure advocated for attachment to basement and foundation wall structures to protect them from moisture is also shown in Agro et al. U.S. Pat. No. 3,561,177.
In U.S. Pat. No. 4,045,964, a subterranean panel drain is illustrated which includes a unitary prefabricated panel having a series of serpentine shaped, vertically extending corrugations in the panel which are open to receive water migrating toward a foundation to which the subterranean panel is attached. A conventional drain pipe is placed at the base of the foundation and is embedded in a gravel pack or body of crushed stone. The gravel pack extends over the lower portion of the panel drain member so as to receive water draining therefrom.
In U.S. Pat. No. 3,563,038, a panel is provided which includes a longitudinal water channeling core having a series of vertically extending channels formed therein. These channels are covered by a water-impervious sheet of material which prevents choking or blocking of the channels by passage of earth or particles of dirt through the sheet material. At the lower end of the channels, a perforated tubular structure is formed integrally with the channel-carrying drain unit to receive water which drains downwardly in the channels. Another patented structure quite similar to that shown in U.S. Pat. No. 3,563,038 is the subterranean wall drain illustrated and described in U.S. Pat. No. 3,654,765.
In U.S. Pat. No. 3,287,866, vertical drainage channels are formed within the foundation wall itself, and at the lower end of these channels they open out into a gravel pack in which a perforated drain pipe is located.
Another construction for protecting a subterranean basement structure at a location where the hydrostatic head of ground water is greatest is shown in U.S. Pat. No. 3,283,460. Here an L-shaped body of a synthetic resin material is constructed to fit between the lower part of the basement wall and the underlying footing. The L-shaped drainage member is provided with channels which are also L-shaped, and which receive any water which has infiltrated the basement wall to the inner side thereof, and drain this water from adjacent the floor slab to a gravel pack and drainage pipe laid under the floor slab.
In all of the cited patents, the systems in use generally require some form of securement of an external block or plate, having grooves and channels formed therein, to the surface of the basement or foundation wall, and then the establishment of communication of the lower end of this plate with a gravel pack. The bed of gravel must be specially laid and positioned for receiving a perforated drainage pipe to collect and remove the water from adjacent the lower part of the foundation wall.